1/4 c. grated Mozzarella cheese
1/3 c. Borden's Parmesan & Romano cheese
3/4 c. mayonnaise
1/2 c. chopped red onion
1 loaf party rye bread

Mix the cheeses, mayonnaise and onion. Spread on rye rounds. Broil until bubbly. Keep warm on hot tray. Serves 4 to 6 guests.